JP7267810B2 - vehicle subframe - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle sub-frame, and more particularly to a vehicle sub-frame mounted on a vehicle such as an automobile while mounting a drive source and the like and supporting a suspension arm and the like.

In recent years, in subframes mounted on vehicles such as automobiles, there are various components such as power system mount related parts such as internal combustion engines and electric motors, suspension related parts such as suspension arms and stabilizers, and steering related parts such as steering gear boxes. external force application parts are attached.

Therefore, such a subframe is required to be attached to the vehicle body in such a manner that its strength and rigidity are increased while its productivity is improved.

Also, for such a subframe, in a typically frontal collision of the vehicle on which it is mounted, it deforms in a desired deformation mode in order to absorb some of the kinetic energy that the vehicle receives in that collision. In other words, it is required to demonstrate the required collision performance.

Under such circumstances, Japanese Unexamined Patent Application Publication No. 2002-100000 discloses a front subframe 16 that includes a side rail 18 arranged along the front side member 12 and a cross member arranged between the front cross member 14 and the front side member 12. The side rails 18 are assembled in a frame shape at 20, and projecting portions 24 are provided at the ends of the side rails 18 on the front side of the vehicle. The energy input to the vehicle body and input to the front side member 12 is attenuated by the axial compression force of the front side member 12 itself, and is also transmitted to the front sub-frame 16 via the bracket 22 on the front side of the vehicle. Disclosed is a configuration in which the energy transmitted as a bending moment about the fixing point and input to the projecting portion 24 is attenuated by the axial compression of the projecting portion 24 itself and then transmitted to the front subframe 16 as an axial compressive force. do.

Further, Patent Document 2 relates to a subframe structure of an automobile. The intermediate portion 6c is formed by bending so as to be positioned downward, and is fastened to the vehicle body side at three points, the intermediate connecting bracket 9 erected in the intermediate portion and the front and rear end portions 6a and 6b. A configuration is disclosed in which groove-shaped bending beads 10a and 10b that are substantially orthogonal to the axial direction are provided at positions on the upper surface and the lower surface that are different in the axial direction between the portion 6a and the intermediate connection bracket 9.

Patent Document 3 relates to a front subframe structure, which includes side members 2L and 2R to which a pair of left and right suspensions extending in the longitudinal direction of the vehicle body are attached, and a cross member 3 constructed between the left and right side members 2L and 2R. The left and right side members 2L and 2R are bent inward and formed in a substantially symmetrical dogleg shape. A configuration in which a fragile portion 4 is formed at 3 is disclosed.

Japanese Utility Model Laid-Open No. 3-91282 JP-A-8-85473 JP-A-2009-61879

However, according to the study of the present inventor, in the configuration of Patent Document 1, energy from the front of the vehicle is absorbed by axial compression along the longitudinal direction of the vehicle via the projecting portion, and then axial compression of the front subframe However, since there is no disclosure or suggestion regarding energy absorption using the bending moment that the front subframe receives, there is room for improvement from the standpoint of increasing energy absorption. be.

Further, in the configurations of Patent Documents 2 and 3, energy absorption using the bending moment received by the subframe is disclosed, but there is no disclosure of energy absorption using axial compression of the subframe. There is room for improvement from the viewpoint of increasing energy absorption.

The present invention has been made through the above studies, and the required collision performance is achieved by combining crushing deformation, which absorbs a large amount of energy during deformation, and bending deformation, which has a high degree of freedom of deformation, while increasing strength and rigidity. It is an object of the present invention to provide a vehicle subframe capable of exhibiting excellent performance.

In order to achieve the above objects, a first aspect of the present invention provides a vehicle subframe mounted on a vehicle body, which is disposed on the front side of the vehicle body in the front-rear direction, and a front member having a front attachment portion attached to both ends in the width direction of the vehicle body on the front side, and each extending in the front-rear direction. While facing each other in the width direction of the vehicle body, each having a rear attachment portion connected to the front member and attached to a portion of the vehicle body on the rear side in the front-rear direction. One side member and a second side member are provided, and the first side member and the second side member are moved by the load applied via the front member at the time of a frontal collision of the vehicle. and a bent portion that bends and deforms in a direction that intersects with the front-rear direction . Each of the first side member and the second side member has a weakened portion against a load, and the rear attachment portion is a widened portion that is gradually widened in the width direction toward the rearward side. The crushed portion is set on the rearward side of the bent portion, and the region where the widened portion starts to expand is defined as the first weakened portion among the weakened portions against the load. In the vehicle subframe, the crushing deformation is continuously generated in the forward direction from the first weakened portion, which serves as a starting point at which deformation starts.

Further, in addition to the first aspect, the present invention provides that, in each of the first side member and the second side member, the crushed portion is provided on the forward side with respect to the first fragile portion. and each of the first side member and the second side member has a cross-sectional area of a longitudinal section taken along a plane orthogonal to the front-rear direction of the general portion other than the weakened portion and the widened portion. The second weakened portion of the weakened portion is set to a portion obtained by subtracting from both sides in the vertical direction of the vehicle body, and the bent portion includes the first side member and the second side member. A second aspect is that a portion obtained by subtracting the cross-sectional area of the longitudinal section from that of the general portion on one side in the vertical direction is set as the third weakened portion of the weakened portion .

Further, in addition to the first or second aspect, the present invention provides a suspension of the vehicle between the crushed portion and the bent portion in each of the first side member and the second side member. A third aspect is that a support portion that supports the member is provided.

In addition to any one of the first to third aspects of the present invention, each of the first side member and the second side member includes a pair of upper vertical wall portions facing each other in the width direction. and an upper member having an upper wall portion connecting between the pair of upper vertical wall portions; and an upper member disposed on the lower side in the vertical direction of the vehicle body with respect to the upper member and mutually in the width direction. a lower member having a pair of lower vertical wall portions facing each other and a lower wall portion connecting between the pair of lower vertical wall portions, wherein the pair of upper vertical wall portions and the pair of lower vertical wall portions are: A fourth aspect is that they are welded at the overlapping portions where they are overlapped correspondingly.

In addition to the fourth aspect of the present invention, the upper member has a pair of upper vertical wall portions and an upper inclined wall portion connecting the upper wall portions between them, and the lower member has A fifth aspect is to have a downwardly inclined wall portion between the pair of lower vertical wall portions and the lower wall portion connecting them.

According to the configuration of the first aspect of the present invention, the vehicle sub-frame mounted on the vehicle body of the vehicle is arranged on the front side in the front-rear direction of the vehicle body to generate a driving force for driving the vehicle. A front member on which a driving source to be generated can be freely mounted, and which has front mounting portions attached to both ends in the width direction of the vehicle body on the front side, and each extending in the front-rear direction and opposed to each other in the width direction of the vehicle body. a first side member and a second side member, each having a rear mounting portion that is connected to the front member and mounted to a portion on the rear side in the front-rear direction of the vehicle body; The first side member and the second side member have a crushed portion that is crushed and deformed in the front-rear direction due to a load applied via the front member at the time of a frontal collision of the vehicle, and is bent in a direction that intersects the front-rear direction. and a deformable bent portion in series, the first side member and the second side member having a weakened portion against load, and the first side member and the second side member each having a fragile portion. , the rear mounting portion is set in the widened portion gradually widened in the width direction toward the rearward side, the crushed portion is set on the rearward side of the bent portion, and the portion where the widening of the widened portion starts is the starting point where the crushing deformation starts as the first weak part among the weak parts against the load, and the crushing deformation is continuously generated forward from the first weak part. While increasing the strength and rigidity of the entire vehicle subframe, the front member is less likely to deform than the first side member and the second side member, typically when an impact force (load) is applied during a frontal collision of the vehicle. Distributedly transmitted to the first side member and the second side member at once via the, it is easy to take a large stroke of crushing deformation (deformation amount in the crushing direction) and to set a high degree of freedom for bending deformation. In the first side member and the second side member, crushing deformation with a large amount of energy absorption during deformation and bending deformation with a high degree of freedom of deformation can be combined, and required collision performance can be exhibited. Thus, crushing deformation can be reliably started in a mode in which the mounting portion of the vehicle sub-frame to the vehicle body is ensured and compatibility with the crushing portion is achieved.

Further, according to the configuration of the second aspect of the present invention, in each of the first side member and the second side member, the crushed portion is adjacent to the first weakened portion on the front side and , the vertical cross-sectional area of each of the first side member and the second side member cut along a plane orthogonal to the longitudinal direction is reduced from that of the general portion other than the weakened portion and the widened portion on both sides in the vertical direction of the vehicle body. The bent portion is set as a second weakened portion of the weakened portion. Since the portion reduced on one side of the is set as the third weakened portion of the weakened portion, the crushing deformation that started at the first weakened portion was inherited by the second weakened portion and continued The crushing deformation can be continued, and the bending deformation can be started in a state where the crushing deformation is substantially completed.

Further, according to the configuration of the third aspect of the present invention, in each of the first side member and the second side member, the support portion for supporting the suspension member of the vehicle is provided between the crushed portion and the bent portion. Since it is set, the suspension member can be supported at an appropriate support point in a manner in which the functions of crushing deformation and bending deformation are reliably exhibited, and the crushing portion, the bending portion, and the suspension member can be supported. Compatibility with the support portion can be achieved.

Further, according to the configuration of the fourth aspect of the present invention, each of the first side member and the second side member has a pair of upper vertical wall portions and a pair of upper vertical wall portions facing each other in the width direction. an upper member having an upper wall portion connecting between them; and a pair of lower vertical wall portions and a pair of lower vertical wall portions disposed on the lower side of the upper member in the vertical direction of the vehicle body and opposed to each other in the width direction. a lower member having a lower wall portion connecting between the vertical wall portions, wherein the pair of upper vertical wall portions and the pair of lower vertical wall portions are welded at overlapping portions where they are correspondingly overlapped. Therefore, each of the first side member and the second side member can be appropriately welded in a state in which the functions of crushing deformation and bending deformation are exhibited.

Further, according to the configuration of the fifth aspect of the present invention, the upper member has a pair of upper vertical wall portions and an upper inclined wall portion connecting the upper wall portions, and the lower member includes a pair of Since the lower vertical wall portion and the lower wall portion have the lower inclined wall portion connecting them, the shape accuracy after molding of each of the first side member and the second side member is improved, The functions of crushing deformation and bending deformation can be exhibited reliably.

FIG. 1 is a plan view showing the configuration of a vehicle subframe according to an embodiment of the present invention. FIG. 2 is a bottom view showing the configuration of the vehicle subframe in this embodiment. FIG. 3 is a left side view showing the configuration of the vehicle subframe in this embodiment. FIG. 4 is a cross-sectional view taken along line AA of FIG. FIG. 5 is a cross-sectional view along BB in FIG. FIG. 6 is a cross-sectional view taken along line CC of FIG. FIG. 7 is a cross-sectional view taken along line DD of FIG.

Hereinafter, a vehicle subframe according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 7 as appropriate. In addition, in the figure, the x-axis, the y-axis and the z-axis form a triaxial orthogonal coordinate system. The positive direction of the x-axis is the right direction of the vehicle body, the positive direction of the y-axis is the front direction of the vehicle body, and the positive direction of the z-axis is the upward direction of the vehicle body. Also, the x-axis direction is sometimes called the width direction or the horizontal direction, the y-axis direction is sometimes called the front-rear direction, and the z-axis direction is sometimes called the vertical direction.

1 to 3 are a plan view, a bottom view and a left side view, respectively, showing the configuration of the vehicle subframe according to this embodiment. FIG. 4 is a cross-sectional view taken along line AA of FIG. 1, which is a longitudinal cross-sectional view cut along a plane parallel to the yz plane formed by the y-axis and the z-axis. 5 to 7 are cross-sectional views from BB to DD in FIG. 1, all of which are vertical cross-sectional views taken along a plane parallel to the xz plane formed by the x-axis and the z-axis. be. In FIGS. 3 to 7, for convenience of explanation, some of the components on the right side of the vehicle sub-frame are indicated by parenthesized reference numerals together with the reference numerals of the left-hand constituent elements as necessary.

As shown in FIGS. 1 to 7, the subframe 1 is attached to a vehicle body such as a front side frame that defines a front bay of a vehicle such as an automobile, and is attached to a driving wheel of the vehicle. It is typically equipped with an electric motor, which is a drive source that generates the applied driving force, and supports a suspension arm or the like. Such a subframe 1 is typically bilaterally symmetrical (plane symmetrical) with respect to a plane that is parallel to the yz plane and passes through a center line that runs longitudinally through the center of the width direction of the vehicle body. have

In the subframe 1, the parts to be mounted on the vehicle body, which will be described later in detail, include a first vehicle body mounting portion A1, a second vehicle body mounting portion A2, a third vehicle body mounting portion A3, a fourth vehicle body mounting portion A4, A fifth vehicle body mounting portion A5 and a sixth vehicle body mounting portion A6 are provided. Four locations S4 are set, and a driving source support portion M1 is also set as a portion for supporting the driving source.

In addition, the subframe 1 is provided with mounting portions for mounting various external force application parts, and the various mounting portions include a steering gear box left mounting portion A7, a steering gear box left mounting portion A7, and a steering gear box left mounting portion A7. A gearbox right mounting portion A8, a stabilizer mounting portion (not shown), and the like are included.

Specifically, the sub-frame 1 mainly extends in the width direction and has left and right extension portions extending in the front-rear direction. A left side member 20 and a right side member 30, which are a pair of side members disposed on the rearward side and opposed to each other in the width direction while extending in the front-rear direction, a cross member 10 and a left connecting member 40 disposed between and connecting the left side members 20, a right connecting member 50 disposed between the cross member 10 and the right side member 30 and connecting them; A front connecting member 60 is provided on the front side of the cross member 10 and connects between the left and right extending portions of the cross member 10 . Each of these members is typically obtained by forming a flat plate member such as a steel plate or a cylindrical member such as steel, and the overlapped or abutted portions correspond to each other. The subframe 1 basically exhibits a closed cross-sectional shape by being welded by arc welding or the like in a contact state to be integrated. Also, the cross member 10, the left connecting member 40, the right connecting member 50, and the front connecting member 60 may collectively be referred to as a front member. Note that the cross member 10, the left connecting member 40, and the right connecting member 50 are not prepared as separate members, but are welded together by arc welding or the like. A pair of upper and lower press-formed products may be welded and integrated by arc welding or the like, or may be produced by casting a metal material or the like. Also, the front connecting member 60 may be omitted if it is not required in terms of component layout, strength, or the like.

Specifically, the cross member 10 includes a lateral portion 11 extending in the width direction, a left front portion 12 located on the left front side of the lateral portion 11 and extending in the front-rear direction, and a A right front portion 13 positioned on the right front side and extending in the front-rear direction, a left connection portion 14 connecting the left end portion of the lateral portion 11 and the rear end portion of the left front portion 12 in a smoothly curved shape, and a lateral portion. a right connecting portion 15 connecting between the right end of the portion 11 and the rear end of the right front portion 13 in a smooth curved shape. That is, the cross member 10 has a convex shape in the rearward direction when viewed from above, and the front end portion of the left front portion 12 and the front end of the right front portion 13 extend through the left connection portion 14, the lateral portion 11, and the right connection portion 15. It is a member that defines an extending direction E extending while bending between the parts and defines an inner region A surrounded by these parts. The drive source may be accommodated in the inner area A, or may be accommodated across the inner area A and part of the area on the rearward side beyond the lateral portion 11 . Further, the impact force applied to the front end of the subframe 1 during a frontal collision of the vehicle is distributed to the lateral portion 11, the left connecting member 40 and the right connecting member 50 via the left front portion 12 and/or the right front portion 13. and then transmitted to the left side member 20 and the right side member 30 as a component in the front-rear direction. Furthermore, the weak portions that are deformable against such impact force are set in the left side member 20 and the right side member 30, but the cross member 10, the left connecting member 40, and the right connecting member 50 other than these are set. and the front connecting member 60 are not set.

At the front end of the left front portion 12 of the cross member 10, a left front mounting member 16 for mounting the subframe 1 to the front end of the left side frame of the vehicle body is arranged in a manner projecting basically toward the upper left. connected. The left front mounting member 16 has a front side member 162 and a rear side member 164 disposed on the rear side thereof, and a through hole 166 is formed in the front side member 162 vertically penetrating therethrough. Similarly, at the front end of the right front portion 13 of the cross member 10, a right front mounting member 17 for mounting the subframe 1 to the front end of the right side frame of the vehicle body is arranged in a manner projecting basically upward and to the right. is set. The structure related to the right front mounting member 17 is a plane parallel to the yz plane and passing through the center line running in the longitudinal direction through the center of the width direction of the vehicle body, in contrast to the structure related to the left front mounting member 16. On the other hand, since it is bilaterally symmetrical, the right front mounting member 17 has a front side member corresponding to the front side member 162, the rear side member 164, and the through hole 166 of the left front mounting member 16, although detailed description thereof will be omitted. 172 , a rear member 174 and a through hole 176 . Each of these members is typically obtained by press-molding a flat plate member such as a steel plate to have a closed cross-sectional shape. However, if necessary, it is formed from a single plate member such as a steel plate or a cylindrical member such as steel instead of two separate plate members such as steel plates. Alternatively, it may be manufactured by casting a metal material or the like.

Here, the cross member 10 having the lateral portion 11, the left front portion 12, the right front portion 13, the left connecting portion 14 and the right connecting portion 15 typically extends in the direction of extension E and the left front portion 12 and Although each front side of the right front portion 13 is open, the upper member 100, which is a plate member such as a steel plate presenting an upward convex shape when viewed as a whole, and a downward direction with respect to the upper member 100. The lower member, which is a plate member such as a steel plate, is arranged to extend in the extending direction E while facing the upper member 100 on the side of the upper member 100. 150 and are typically welded by arc welding or the like to be integrated. If necessary, the upper member 100 and the lower member 150 may be formed from a single tubular member made of steel instead of two separate plate members such as steel plates. It may be manufactured at one time by casting a metal material or the like.

The upper member 100 has an upper wall portion 102, an inner wall portion 104 that continues to the upper wall portion 102 on the side of the inner region A and extends downward or obliquely downward, and faces the inner wall portion 104 on the opposite side of the inner region A. It also has an outer wall portion 106 that continues to the upper wall portion 102 and extends downward or obliquely downward. The outer wall portion 106 is provided with an outer flange 108 extending from its lower end toward the opposite side of the inner region A. As shown in FIG. The upper wall portion 102 of the lateral portion 11 is provided with a pedestal member 120 having a through hole 110 formed coaxially with a through hole (not shown) extending vertically through the upper wall portion 102 . The upper wall portion 102 of the left front portion 12 is formed with a through hole 112 penetrating therethrough in the vertical direction, and the upper wall portion 102 of the right front portion 13 is formed with a through hole 114 penetrating therethrough in the vertical direction. . Also, in FIG. The leftmost R stop portion (R stop line) of the bending R applied to at least a part between the outer wall portion 106 at the right connection portion 15 and the outer wall portion 106 at the right connection portion 15 is indicated by L, respectively.

The lower member 150 has a lower wall portion 152, an inner wall portion 154 that continues to the lower wall portion 152 on the side of the inner region A and extends upward or obliquely upward, and faces the inner wall portion 154 on the opposite side of the inner region A. An outer wall portion 156 extending upward or obliquely upward while continuing to the inner wall portion 154, and an outer flange 158 extending from the upper end of the outer wall portion 156 toward the opposite side of the inner region A. In view, inner wall 154 and outer wall 156 have contours similar to those of inner wall 104 and outer wall 106 of top member 100 . A through-hole 160 is formed in the lower wall portion 152 of the lateral portion 11 so as to pass through the lower wall portion 152 in the vertical direction and into which the lower end portion of the base member 120 is inserted. A collar member 190 having a through hole 182 coaxial with the through hole 112 of the upper wall portion 102 is provided in the lower wall portion 152 of the left front portion 12 , and a collar member 190 having a through hole 182 coaxial with the through hole 112 of the upper wall portion 102 is provided in the lower wall portion 152 of the left front portion 12 . A collar member 192 is provided having a throughbore 184 coaxial with bore 114 . Also, the upper member 100 and the lower member 150 are arranged at the ends of the overlapping portions of the inner wall portion 104 and the inner wall portion 154 on the side of the inner region A, and the outer flange 108 and the outer flange 158 on the opposite side of the inner region A. The ends of the overlapping portions are welded together by arc welding or the like to define a closed cross-section that is open at the front left portion 12 and the front right portion 13 but closed otherwise.

The left front mounting member 16 is positioned on the left front side of a closed cross section defined by the upper wall portion 102, the inner wall portion 104 and the outer wall portion 106 of the upper member 100 and the lower wall portion 152, the inner wall portion 154 and the outer wall portion 156 of the lower member 150. The lower member 150 abuts on the front left end of the wall portion in a manner that closes the opening, and is placed on a part of the front end portion of the lower wall portion 152 of the lower member 150 . The parts are integrated by welding, typically by arc welding or the like, and may be handled as part of the cross member 10 . Such an integrated structure also holds true for the right front mounting member 17 that abuts on the right front ends of these walls.

The front connecting member 60 is typically made of a tubular member made of steel or the like. A bracket 68 made of steel or the like is provided. The brackets 64 and 68 are welded to the upper surface of the front connecting member 60 by arc welding or the like, and together with the base member 120 disposed on the upper wall portion 102 of the lateral portion 11 of the cross member 10, the subframe 1 is defined. It functions as a mounting member for mounting the drive source housed in the inner region A and the like on the sub-frame 1 . The left end of the front connecting member 60 is inserted into the right end of the front left mounting member 16 and welded by arc welding or the like to integrate the front left mounting member 16 and the front connecting member 60 . Such an integrated configuration is the same for the right front mounting member 17 having a left end portion into which the right end portion of the front connecting member 60 is nested. The left end portion and right end portion of the front connecting member 60 may be connected correspondingly to the left front portion 12 and right front portion 13 of the cross member 10 to connect them.

In addition, the left connecting member 40 typically has a lateral length (width in the width direction) on the rearward side of the cross member 10 that decreases from the front toward the rear. An inner edge portion 41 which is an edge portion on the right side in the width direction and whose front end portion is an inner front end portion P (shown in FIGS. 1 and 2), and an edge portion on the left side in the width direction A certain outer edge portion 42 is defined and connected to the left rear end portion of the cross member 10, and has an upwardly convex shape when viewed as a whole, although its longitudinal side is open. An upper member 400, which is a plate member such as a steel plate, is arranged on the lower side of the upper member 400 so as to face the upper member 400, and has a downwardly convex shape when viewed as a whole like the upper member 400. The lower member 450, which is a plate member such as a steel plate exhibiting If necessary, the upper member 400 and the lower member 450 may be formed from a single plate member such as steel instead of two separate plate members such as steel plates. It may be manufactured at one time by casting a metal material or the like.

Here, the upper member 400 includes an upper wall portion 402 and an intermediate wall that extends obliquely downward and surrounds the upper wall portion 402 on both sides in the width direction and on the rear side while continuing from the upper wall portion 402 . It has a portion 406, and a flange 408 which surrounds the intermediate wall portion 406 on both sides in the width direction and on the rear side while continuing to the lower end of the intermediate wall portion 406 and extending to the outside of the plate.

The lower member 450 includes a lower wall portion 452, an intermediate wall portion 456 that surrounds the lower wall portion 452 on both sides in the width direction and on the rear side while extending obliquely upward while continuing from the lower wall portion 452, It also has flanges 458 extending from the upper end of the intermediate wall portion 456 to the outside of the plate and surrounding the intermediate wall portion 456 on both sides in the width direction and on the rear side.

The upper member 400 and the lower member 450 are integrated by arc welding or the like at the overlapped ends of the flanges 408 and 458, except for their front and rear ends. It defines a closed cross-section that is open at the rear and rear ends but otherwise closed. At the front ends of the upper member 400 and the lower member 450 , the upper surface of the upper wall portion 402 , the intermediate wall portion 406 and the flange 408 of the upper member 400 meet the lower surface of the outer flange 108 of the upper member 100 of the cross member 10 . They are typically welded by arc welding or the like in an abutting manner, and the upper surface of the lower wall portion 452 of the lower member 450 abuts the lower surface of the lower wall portion 152 of the lower member 150 of the cross member 10 . are typically welded by arc welding or the like so that the front and rear ends thereof are integrated with the cross member 10 in a closed manner.

On the upper surfaces of the upper wall portion 402 and the intermediate wall portion 406 of the upper member 400, a left center mounting member 44 for mounting the subframe 1 to the intermediate portion of the left side frame of the vehicle body is basically mounted on the upper left. It is arranged in a manner projecting toward the direction. The left middle mounting member 44 has a front inner member 442 and a rear inner member 444 disposed on the rearward side thereof. In the left middle mounting member 44, an outer member 446 is disposed on the left side with respect to the front inner member 442 and the rear inner member 444, and the rear inner member 444 and the outer member 446 vertically pass through them. A through hole 448 is formed, and a notch portion C is formed by cutting out the peripheral edge portion on the left side of the through hole 448 . Each of these members is typically obtained by press-molding a single flat plate member such as a steel plate, and is welded and integrated one by one by arc welding or the like. If necessary, it may be formed from a single plate member such as a steel plate instead of three separate plate members such as steel plates, or it may be manufactured by casting a metal material or the like. can be anything. The cutout portion C is fragile for releasing a fastener such as a bolt inserted through the through hole 448 by an impact force applied to and transmitted to the front end portion of the subframe 1 at the time of a frontal collision of the vehicle. It functions as a department.

On the front side of the left middle mounting member 44, the flange 458 of the lower member 450 extends leftward from the flange 408 of the upper member 400. A left front support member 46 is provided defining an opening for partial mounting. The left front support member 46 has a front side member 462 that forms the front wall and upper wall of the opening, and a rear side member 464 that is arranged on the rear side thereof and forms the rear wall of the opening. A nut 466 is provided on the rear member 464 , and corresponding through holes (not shown) are formed in the front member 462 and the rear member 464 . Each of these members is typically obtained by press-molding a single flat plate member such as a steel plate, and is welded and integrated one by one by arc welding or the like. If necessary, it may be formed from a single plate member such as a steel plate instead of two separate plate members such as steel plates, or it may be manufactured by casting a metal material or the like. can be anything.

The configuration associated with the right connecting member 50, the right middle mounting member 54 and the right front support member 56 is parallel to the yz plane with respect to the configuration associated with the left connecting member 40, the left middle mounting member 44 and the left front support member 46. symmetrical with respect to a plane passing through the center line running in the longitudinal direction through the center of the width direction of the vehicle body. The member 54 and the right front support member 56 have an inner edge portion 41 , an outer edge portion 42 , an upper member 400 , an upper wall portion 402 , an intermediate wall portion 406 , a flange 408 , a lower member 450 , a lower wall portion 452 , an intermediate wall portion 456 and a flange 458 . , the front inner member 442, the rear inner member 444, the outer member 446, the through hole 448, the notch C, the front side member 462, the rear side member 464, and the nut 466, the inner edge portion 51, the outer edge portion 52, the upper member 500 , upper wall portion 502, intermediate wall portion 506, flange 508, lower member 550, lower wall portion 552, intermediate wall portion 556, flange 558, front inner member 542, rear inner member 544, outer member 546, through hole 548, notch Part C has a front member 562 , a rear member 564 and a nut 566 .

Also, the left side member 20 is typically applied to the front end of the subframe 1 and transmitted to the left side member 20 from the rear side to the front side at the time of a frontal collision of the vehicle. It has a crushing portion that is crushed and deformed in the front-rear direction by an impact force, and a bent portion that is bent in a direction intersecting the front-rear direction due to the impact force, and is connected to the left connecting member 40 at its front end. there is The width of the left side member 20 is typically gradually increased from the width of the general portion G of the left side member 20 toward the rear in order from the rear end toward the front, and A widened portion 21 for attaching the subframe 1 to the rear end portion of the left side frame of the vehicle body or to the lower front portion of the vehicle compartment, and a portion (width start portion) where the width of the widened portion 21 starts to expand rearward. The left side member 20 becomes a starting point at which the left side member 20 begins to crush and deform in the longitudinal direction due to the longitudinal component of the impact force applied to the front end of the subframe 1 and transmitted to the left side member 20 at the time of a frontal collision of the vehicle. A first weakened portion 22, a second weakened portion 23 for continuously generating the crushing deformation of the left side member 20 initiated by the first weakened portion 22, and the front end of the subframe 1 in the event of a frontal collision of the vehicle. The front-rear direction component of the impact force applied to the left side member 20 and transmitted to the left side member 20 causes the left side member 20 to bend and deform in the direction intersecting the front-rear direction. I have. In the left side member 20, the portion other than the widened portion 21, the first weakened portion 22, the second weakened portion 23, and the third weakened portion 24 is a general portion G having a longitudinal section with a substantially constant area. From the viewpoint of reliably receiving the impact applied to the front end portion of the subframe 1 and transmitted to the left side member 20 in the event of a frontal collision of the vehicle, the general portion G includes the upper wall portion of the left side member 20 and the Preferably, the lower wall is parallel to the xy plane, and the left and right walls of the left side member 20 are parallel to the yz plane. From the viewpoint of reliably receiving the impact force applied to the front end of the subframe 1 and transmitted to the left side member 20 in the event of a frontal collision of the vehicle, the left side member 20 is the left front portion of the cross member 10 when viewed from the front. It is preferably within the range of 12. Further, from the viewpoint of achieving both the collision performance of the subframe 1 and the layout property of the suspension member, it is necessary to mount a part of the left suspension member between the second weakened portion 23 and the third weakened portion 24. is preferably set.

The left side member 20 is open on both sides in the front and rear directions. A lower member 250, which is a plate member such as a steel plate that is disposed facing the lower side of the upper member 200 and has a downwardly convex shape when viewed as a whole, is the same as the upper member 200. , typically by being welded by arc welding or the like to be integrated. If necessary, the upper member 200 and the lower member 250 may be formed from a single cylindrical member such as steel instead of two separate plate members such as steel plates. It may be manufactured at one time by casting a metal material or the like.

Here, the upper member 200 includes an upper wall portion 202, an inner wall portion 204 extending downward from the upper wall portion 202 on the right side, and an inner wall portion 204 extending from the upper wall portion 202 on the left side. 204 has an outer wall portion 206 that faces widthwise thereof. The lower member 250 includes a lower wall portion 252 , an inner wall portion 254 that rises continuously with the lower wall portion 252 on the right side, and an inner wall portion 254 that continues with the lower wall portion 252 on the left side and rises. It has outer wall portions 256 that are directionally opposed. In addition, in the event of a frontal collision of the vehicle, it functions as a crushing portion that is crushed and deformed in the front-rear direction against the impact applied to the front end portion of the subframe 1 and transmitted to the left side member 20. From the viewpoint of reliably exhibiting the function as a bent portion that bends and deforms in the direction, the upper member 200 and the lower member 250 have an overlapping portion where the lower end of the inner wall portion 204 overlaps the upper end of the inner wall portion 254. In addition, it is preferable that the lower end portion of the outer wall portion 206 forms an overlapping portion overlapping the upper end portion of the outer wall portion 256, and the lower end portion of each overlapping portion is welded by arc welding or the like to be integrated. In addition, it is possible to suppress the intrusion of moisture or the like from the upward side between the overlapping portions. In addition, from the viewpoint of increasing the precision of the molding shape of the left side member 20 and ensuring that the function as the crushing portion and the function as the bending portion are exhibited, the upper member 200 and the lower member 250 are formed by the upper wall portion 202 and the inner wall portion. Between the portion 204, between the upper wall portion 202 and the outer wall portion 206, between the lower wall portion 252 and the inner wall portion 254, and between the lower wall portion 252 and the outer wall portion 256, respectively, so that their corners are chamfered. It is preferable to connect with an inclined wall portion S. A plurality of such inclined wall portions S may be provided with different inclination angles between these wall portions. In addition, welding of the overlapped portion where the lower end of the inner wall portion 204 overlaps with the upper end of the inner wall portion 254 and the overlapped portion where the lower end of the outer wall portion 206 overlaps with the upper end of the outer wall portion 256 includes the overlapped portion itself. may be welded by plug welding or the like.

In the widened portion 21 of the upper member 200 of the left side member 20, the distance between the inner wall portion 204 and the outer wall portion 206 is gradually increased toward the rear, so that the upper wall portion 202 is widened and vertically expanded. A collar member 224 having a through hole 222 and a collar member 228 having a through hole 226 are arranged coaxially with a through hole (not shown). In the widened portion 21 of the lower member 250 of the left side member 20, the distance between the inner wall portion 254 and the outer wall portion 256 is gradually increased toward the rear so that the lower wall portion 252 is widened and the collar member 224 is provided. A through hole 272 and a through hole 276 are formed coaxially with the through hole 222 of the collar member 228 and the through hole 226 of the collar member 228 . The frontmost portion of the widened portion 21 is a portion where the width of the widened portion 21 begins to expand rearward (width expansion start portion). Shown as a widening start point 210 and an outer widening start point 212 on the leftward side, respectively. The width of the inner width expansion start portion 210 and the outer width expansion start portion 212 increases in the rearward direction of the widened portion 21, and the through holes are located on the rear side of the inner width expansion start portion 210 and the outer width expansion start portion 212. At positions 222, 226, 272 and 276, the widened portion 21 is attached to the rear end portion of the left side frame of the vehicle body and to the front lower portion of the passenger compartment and restrained. The front end of the frame 1 receives the force applied to the front end of the frame 1 and transmitted to the left side member 20. This is the portion where stress is most concentrated. Due to the components, the left side member 20 functions as the first weakened portion 22, which is a starting point at which the left side member 20 begins to be crushed and deformed in the front-rear direction. In addition, in the first weakened portion 22, when an impact force is transmitted to the left side member 20, the inner wall portion 204 and the inner wall portion 254 are deformed so as to dent leftward due to the component in the front-rear direction. , the outer wall portion 206 and the outer wall portion 256 are deformed so as to be recessed rightward, and accordingly, the upper wall portion 202 is deformed so as to protrude upward, and the lower wall portion 252 is deformed downward. This will cause a crushing deformation that deforms so as to protrude toward.

As shown in FIG. Compared to the member 200 in the general portion G, the upper wall portion 202 is recessed downward to a predetermined recess depth (length in the vertical direction). The inclination angle of the inclined wall portion S between the portion 204 and the inclination angle of the inclined wall portion S between the upper wall portion 202 and the outer wall portion 206 are gentle, and the lower member 250 is compared with that in the general portion G. Then, the lower wall portion 252 is recessed upward to the same recess depth as the predetermined recess depth of the upper wall portion 202 , and accordingly the inclination between the upper wall portion 202 and the inner wall portion 254 is formed. The inclination angle of the wall portion S and the inclined wall portion S between the upper wall portion 202 and the outer wall portion 256 are gentle. That is, in the second fragile portion 23, the distance (vertical distance) between the upper wall portion 202 of the upper member 200 and the lower wall portion 252 of the lower member 250 is higher than the outer contour of the general portion G. Equally reduced, the shape of the outer contour of the second fragile portion 23 forms a recess 214 and a recess 264, and the area of the longitudinal section of the left side member 20 taken along a plane parallel to the xz plane is , is isotropically reduced in the vertical direction with respect to that of the general part G. Since the recessed portion 214 and the recessed portion 264 have a vertical cross-sectional shape with an area that is isotropically reduced in the vertical direction, the crushing deformation of the left side member 20 initiated by the first weakened portion is induced. When the impact force is transmitted to the left side member 20, the front-rear component of the impact force causes the upper wall of the recessed portion 214 to collapse, following the crushing deformation of the first fragile portion 22. The portion 202 and the inclined wall portion S are deformed so as to be recessed downward, and the lower wall portion 252 and the inclined wall portion S of the recess portion 264 are deformed so as to be recessed upward. The portion 204 and the inner wall portion 254 are deformed to protrude rightward, and the outer wall portion 206 and the outer wall portion 256 are deformed to protrude leftward. Further, when crushing deformation combined with such uneven deformation occurs continuously, the left side member 20 on the front side of the second fragile portion 23 is further deformed by such uneven deformation. A combination of crushing deformation will occur continuously.

In the third weakened portion 24 arranged on the front side with respect to the second weakened portion 23, as shown in FIG. It is recessed downward to a predetermined recess depth (length in the vertical direction). The inclination angle of the inclined wall portion S between 202 and the outer wall portion 206 is gentle. However, in the third fragile portion 24, unlike the second fragile portion 23, the lower wall portion 252 is not recessed upward. That is, in the third fragile portion 24, the distance (vertical distance) between the upper wall portion 202 of the upper member 200 and the lower wall portion 252 of the lower member 250 is Since only the upper wall portion 202 is recessed, the shape of the outer contour of the third fragile portion 24 forms a concave portion 216, and the left side member 20 is placed on a plane parallel to the xz plane. The area of the longitudinal section cut by is anisotropically reduced in the vertical direction with respect to that of the general portion G, and the area of the longitudinal section is the first weakened portion 22 and the second weakened portion 23 is set larger than the area of each longitudinal section of The concave portion 216 has a vertical cross-sectional shape that is anisotropically reduced in size and has an area larger than the vertical cross-sectional area of each of the first weakened portion 22 and the second weakened portion 23 . Therefore, after at least most of the crushing deformation of the left side member 20 is completed, the upper wall portion 202 and the inclined wall portion S of the concave portion 216 are deformed so as to be concave downward. The lower wall portion 252 and the inclined wall portion S of 1 are deformed so as to protrude downward. It should be noted that the recess 216 is not provided in the upper member 200 but is provided in the inner wall portion 204 and the inner wall portion 254 and the outer wall portion 206 and the outer wall portion of the upper member 200 and the lower member 250, respectively, depending on the required direction of the bending deformation of the left side member 20 . 256, or lower member 250. Moreover, from the viewpoint of ensuring that the crushing deformation of the left side member 20 occurs over a wide area, the distance in the front-rear direction between the second weakened portion 23 and the third weakened portion 24 is It is preferably set longer than the distance in the front-rear direction of the second fragile portion 23 . Further, the lower member 250 has a shape in which the width of the upper member 200 is narrowed by the thickness of the upper member 200 on the left and right sides and the third fragile portion 24 is omitted and the shape is inverted upside down. In addition, the upper wall portion 202, the lower wall portion 252, the inner wall portion 204, the inner wall portion 254, the outer wall portion 206, the outer wall portion 256, and the inclined wall portion S are the widened portion 21, the first weakened portion 22, and the second weakened portion. It is a flat surface except for 23 and the third weakened portion 24 .

In the left side member 20, through-holes 230 and 232 that penetrate vertically through the upper wall portion 202 of the upper member 200 are typically provided between the second weakened portion 23 and the third weakened portion 24; Through-holes 280 and 282 are formed through the lower wall portion 252 of the lower member 250 in the vertical direction and are coaxial with the through-holes 230 and 232 .

The structure related to the right side member 30 is a plane parallel to the yz plane and passing through the center line running longitudinally through the center of the width direction of the vehicle body, with respect to the structure related to the left side member 20. On the other hand, the right side member 30 has a widened portion 21, a first weakened portion 22, a second weakened portion 23, and a third weakened portion 24, although detailed description thereof is omitted because it is bilaterally symmetrical. , upper member 200 , lower member 250 , upper wall portion 202 , lower wall portion 252 , inner wall portions 204 and 254 , outer wall portions 206 and 256 , inclined wall portion S, inner widening start portion 210 , outer widening start portion 212 , recess 214 , 216 , 264 and 266 , through holes 222 , 226 , 230 , 232 , 272 , 276 , 280 and 282 , collar members 224 and 228 , widened portion 31 , first weakened portion 32 and second weakened portion. Part 33, third fragile portion 34, upper member 300, lower member 350, upper wall portion 302, lower wall portion 352, inner wall portions 304 and 354, outer wall portions 306 and 356, inclined wall portion S, inner widening start portion 310 , widening start portion 312 , recesses 314 , 316 , 364 and 366 , through holes 322 , 326 , 330 , 332 , 372 , 376 , 380 and 382 , and collar members 324 and 328 .

In the above configuration, among the various parts where the subframe 1 is mounted on the vehicle body, the left front first vehicle body mounting portion A1 corresponds to the through hole 166 provided in the front side member 162 of the left front mounting member 16, and the right front The second vehicle body mounting portion A2 corresponds to the through hole 176 provided in the front member 172 of the right front mounting member 17, and the middle left third vehicle body mounting portion A3 corresponds to the rear inner member of the left middle mounting member 44. 444 and the through holes 448 provided in the outer member 446 correspond to the right middle fourth vehicle body mounting portion A4, and the through holes 548 provided in the rear inner member 544 and the outer member 546 of the right middle mounting member 54 are used as the fourth vehicle body mounting portion A4. Correspondingly, the through holes 222, 226, 272, 276 provided in the widened portion 21 of the left side member 20 and the collar members 224 and 228 correspond to the left rear fifth vehicle body mounting portion A5, and the right rear fifth vehicle body mounting portion A5 corresponds to The through holes 322, 326, 372, 376 provided in the widened portion 31 of the right side member 30 and the collar members 324 and 328 correspond to the sixth vehicle body attachment portion A6. These parts are typically parts for fastening using fastening members such as bolts. Moreover, as these parts, an example in which a rigid structure is adopted without interposing a subframe mounting member is assumed, but a floating structure in which a subframe mounting member is interposed may be adopted.

In addition, among the various portions where the subframe 1 supports the inner pivot portions of the suspension arms, the left front first support portion S1 is an opening formed by the front side member 462 and the rear side member 464 of the left front support member 46. and the through hole and the nut 466 provided therein correspond, and as the right front second support portion S2, the opening defined by the front side member 562 and the rear side member 564 of the right front support member 56 and the opening provided there The through holes and the nut 566 correspond to the left rear third support portion S3. , and 282, and through holes 330 and 332 provided in the upper wall portion 302 of the right side member 30 and through holes 380 and 382 provided in the lower wall portion 352 of the right rear fourth support portion S4. corresponds to These parts are typically parts for fastening using fastening members such as bolts. In addition, although an example in which an L-shaped lower arm is employed as the suspension arm applied to these parts is assumed, an A-shaped lower arm or two I-shaped lower arms may be employed. Further, assuming an example in which inner cylinders of insulator bushing members (not shown) are respectively fastened to the left front first support portion S1 and the right front second support portion S2, the left rear third support portion S3 and the right rear third support portion S3 are assumed to be fastened respectively. In the fourth support portion S4, although illustration is omitted, an example is assumed in which brackets are respectively fastened and an insulator bush member is attached to each of the brackets.

In addition, among various mounting portions to which various external force application parts are mounted, the subframe 1 includes a through hole 112 provided in the upper wall portion 102 of the left front portion 12 of the cross member 10 and a steering gear box left mounting portion A7. The through hole 182 provided in the lower wall portion 152 and the collar member 190 correspond to the right mounting portion A8 of the steering gearbox. The through hole 184 provided in the wall portion 152 and the collar member 192 correspond. These parts are typically parts for fastening using fastening members such as bolts.

Further, as the drive source support portion M1 in which the subframe 1 supports the drive source, the through hole 110 and the base member 120 provided in the upper wall portion 102 and the lower wall portion 152 of the lateral portion 11 of the cross member 10 are provided. The brackets 64 and 68 provided in the front connecting member 60 and the through holes 62 and 66 correspond to the through hole 160 provided in the front connecting member 60 . These parts are typically parts for fastening using fastening members such as bolts. Further, the through hole 110 and the pedestal member 120 provided in the upper wall portion 102 of the lateral portion 11 of the cross member 10 may also be used as the drive source support portion M1 as the rear mounting portion of the steering gearbox.

In the subframe 1 according to the present embodiment described above, a drive source that is disposed on the front side in the longitudinal direction of the vehicle body and generates a driving force for driving the vehicle can be mounted. front members 10, 40, 50, 60 having front mounting portions attached to both ends in the width direction of the vehicle body; a first side member 20 and a second side member 30 each having a rear attachment portion connected to each of 10, 40, 50, and 60 and attached to a portion on the rear side in the longitudinal direction of the vehicle body; The first side member 20 and the second side member 30 are provided with crushed portions ( a section including the weakened portions 22, 23 and the weakened portions 32, 33) and a bending portion (a section including the weakened portion 24 and the weakened portion 34) that bends and deforms in a direction intersecting the front-rear direction. Therefore, while increasing the strength and rigidity of the entire subframe 1, the shock force typically applied during a frontal collision of the vehicle is more difficult to deform than the first side member and the second side member. Through the front members 10, 40, 50, 60, the first side member 20 and the second side member 30 are distributed and transmitted at once, and it is easy to obtain a large stroke of the crushing deformation (deformation amount in the crushing direction), In addition, by using the first side member 20 and the second side member 30, which can easily set a high degree of freedom in bending deformation, it is possible to combine crushing deformation with a large amount of energy absorption during deformation and bending deformation with a high degree of freedom in deformation. It is possible to exhibit the required collision performance.

In addition, in the subframe 1 according to the present embodiment, the first side member 20 and the second side member 30 have weakened portions 22, 23, 24, 32, 33, and 34 against the load at the time of frontal collision, In each of the first side member 20 and the second side member 30, the rear attachment portions A5 and A6 are set at the widened portions 21 and 31 that are gradually widened in the width direction toward the rear side, and the crushed portion (the section including the weakened portions 22 and 23 and the weakened portions 32 and 33) is set on the rearward side of the bent portion (the section including the weakened portion 24 and the weakened portion 34). of the fragile portions 22, 23, 24, 32, 33, and 34 against the load at the time of frontal collision, and the first fragile portion 22, 32 can start crushing deformation. It is possible to reliably start the crushing deformation in a mode in which the mounting portion of the frame 1 is secured and compatibility with the crushing portion is achieved.

In addition, in the subframe 1 according to the present embodiment, in each of the first side member 20 and the second side member 30, the crushed portion (the section including the weakened portions 22 and 23 and the weakened portions 32 and 33) has a second The cross-sectional area of a longitudinal section obtained by cutting each of the first side member 20 and the second side member 30 along a plane perpendicular to the front-rear direction and adjacent to the first weakened portion 22, 32 on the front side is The fragile portions 22, 23, 24, 32, 33 are reduced on both sides in the vertical direction of the vehicle body from the general portion G other than the fragile portions 22, 23, 24, 32, 33, 34 and the widened portions 21, 31. , 34 are set, and in the bent portion (section including the weakened portion 24 and the weakened portion 34), each of the first side member 20 and the second side member 30 The third weakened portions 24, 34 among the weakened portions 22, 23, 24, 32, 33, 34 are set at one side in the vertical direction where the cross-sectional area of the longitudinal section is reduced from that of the general portion G. Therefore, the crushing deformation that started at the first weakened portions 22 and 32 can be inherited by the second weakened portions 23 and 33 to continue as a continuous crushing deformation, and the crushing deformation is substantially Once completed, the bending deformation can be initiated.

In addition, in the subframe 1 according to the present embodiment, in each of the first side member 20 and the second side member 30, the crushed portion (the section including the weakened portions 22, 23 and the weakened portions 32, 33) and the bent portion Since the support portions S3 and S4 for supporting the suspension members of the vehicle are set between the portions (sections including the weakened portion 24 and the weakened portion 34), the function of crushing deformation and bending deformation can be reliably exhibited. In this manner, the suspension member can be supported at appropriate support points, and the crushed portion (the section including the weakened portions 22, 23 and the weakened portions 32, 33) and the bent portion (including the weakened portion 24, the weakened portion 34). section) and the support portions S3 and S4 that support the suspension members.

In addition, in the subframe 1 according to the present embodiment, each of the first side member 20 and the second side member 30 includes a pair of upper vertical wall portions 204, 206, 304, 306 and a pair of upper vertical wall portions 204, 206, 304, 306 facing each other in the width direction. upper members 200, 300 having upper wall portions 202, 302 connecting between upper vertical wall portions 204, 206, 304, 306; A pair of lower vertical wall portions 254, 256, 354, 356 that are disposed and face each other in the width direction and lower wall portions 252, 352 that connect between the pair of lower vertical wall portions 254, 256, 354, 356 and a pair of upper longitudinal wall portions 204, 206, 304, 306 and a pair of lower longitudinal wall portions 254, 256, 354, 356 correspondingly superimposed on each other. Since they are welded at the mating portion, each of the first side member 20 and the second side member 30 can be appropriately welded in a state in which the functions of crushing deformation and bending deformation are exhibited.

In addition, in the subframe 1 of the present embodiment, the upper members 200 and 300 are arranged between the pair of upper vertical wall portions 204, 206, 304 and 306 and the upper inclined wall portion connecting them. S, and the lower member 250, 350 has a pair of lower vertical walls 254, 256, 354, 356 and a lower inclined wall S between the lower walls 252, 352 connecting them. , the shape accuracy of each of the first side member 20 and the second side member 20 after molding can be improved, and the functions of crushing deformation and bending deformation can be reliably exhibited.

It should be noted that the present invention is not limited to the above-described embodiments in terms of the types, shapes, arrangements, number, etc. of the members. Needless to say, it can be changed as appropriate within a range that does not deviate.

As described above, in the present invention, it is possible to exhibit the required collision performance by combining crushing deformation, which absorbs a large amount of energy during deformation, and bending deformation, which has a high degree of freedom of deformation, while enhancing strength and rigidity. Since it is possible to provide a vehicle subframe that can be used, it is expected to be widely applied to the field of subframes for moving bodies such as vehicles due to its universal character.

Reference Signs List 1 Subframe 10 Cross member 11 Lateral portion 12 Front left portion 13 Front right portion 14 Left connection portion 15 Right connection portion 16 Front left mounting member 17 Front right mounting member 20 Left side member 30 Right side member 21, 31... Widened parts 22, 32... First weakened parts 23, 33... Second weakened parts 24, 34... Third weakened part 40... Left connecting member 41... Inner edge part 42... Outer edge part 44... Center left Mounting member 46 Left front supporting member 50 Right connecting member 51 Inner edge portion 52 Outer edge portion 54 Right middle mounting member 56 Right front supporting member 100 Upper member 102 Upper wall portion 104 Inner wall portion 106 Outer wall portion 108 Outer flanges 110, 112, 114 Through hole 120 Base member 150 Lower member 152 Lower wall portion 154 Inner wall portion 156 Outer wall portion 158 Outer flange 160 Through hole 162 Front member 164 Rear member 166 Through hole 172 Front member 174 Rear member 176, 182, 184 Through hole 190, 192 Collar member 200 Upper member 202 Upper wall portion 204 Inner wall portion 206 Outer wall portion 210 Inner widening start portion 212 Outer width start portions 214, 216... Recesses 222, 226... Through holes 224... Collar members 226, 228, 230... Through holes 250... Lower member 252... Lower wall part 254... Inner wall part 256... Outer wall part 264... Recesses 272, 280 through hole 300 upper member 302 upper wall portion 304 inner wall portion 306 outer wall portion 310 inner widening start portion 312 outer widening start portion 314 recesses 322, 330 through hole 324 collar member 330 through hole 350 Lower member 352 Lower wall portion 380 Through hole 400 Upper member 402 Upper wall portion 406 Intermediate wall portion 408 Flange 442 Front inner member 444 Rear inner member 446 Outer member 448 Through hole 450 Bottom Member 452 Lower wall 456 Intermediate wall 458 Flange 462 Front member 464 Rear member 466 Nut 500 Upper member 502 Upper wall 506 Intermediate wall 508 Flange 542 Front inner member 544 Rear inner member 546 Outer member 548 Through hole 550 Lower member 552 Lower wall portion 556 Intermediate wall portion 558 Flange 562 Front member 564 Rear member 566 Nut A1 First vehicle body mounting portion A2 Second 2 vehicle body mounting portion A3 3rd vehicle body mounting portion A4 4th vehicle body mounting portion A5 5th vehicle body mounting portion A6 6th vehicle body mounting portion A7 steering gear box left mounting portion A8 steering gear box right mounting portion S1 1st support part S2...2nd support part S3...3rd support part S4...4th support part M1...Drive source support part

Claims (5)

A vehicle subframe mounted on a vehicle body,
A drive source that is disposed on the front side in the front-rear direction of the vehicle body and generates a driving force for driving the vehicle can be mounted. a front member having a front mounting portion attached thereto;
Each extends in the front-rear direction and is disposed facing each other in the width direction of the vehicle body, connected to the front member, and attached to a portion of the vehicle body on the rear side in the front-rear direction. a first side member and a second side member each having a rear mounting portion;
with
The first side member and the second side member intersect in the front-rear direction with the crushed portion that is crushed and deformed in the front-rear direction by a load applied via the front member at the time of a frontal collision of the vehicle. and a bending portion that bends and deforms in the direction of
The first side member and the second side member each have a weakened portion against the load,
In each of the first side member and the second side member, the rear attachment portion is set at a widened portion that is gradually widened in the width direction toward the rearward side,
The crushed portion is set on the rearward side of the bent portion, and the crushing deformation starts with a portion where the widened portion starts to expand as a first weakened portion among the weakened portions against the load. and the crushing deformation is continuously generated in the forward direction from the first weakened portion . In each of the first side member and the second side member, the crushed portion is adjacent to the first weakened portion on the forward side, and the first side member and the second side member 2 of each side member taken along a plane perpendicular to the longitudinal direction, the cross-sectional area of the longitudinal section is reduced from that of the general portion other than the weakened portion and the widened portion on both sides in the vertical direction of the vehicle body. It is set as a second weakened portion of the weakened portion, and in the bent portion, the cross-sectional area of the longitudinal section of each of the first side member and the second side member is different from that of the general portion. 2. The vehicle subframe according to claim 1 , wherein the portion that is reduced on one side in the vertical direction is set as a third weakened portion of the weakened portion. 3. The vehicle according to claim 1, wherein each of said first side member and said second side member is provided with a supporting portion between said crushed portion and said bent portion for supporting a suspension member of said vehicle. vehicle subframe. Each of the first side member and the second side member is an upper member having a pair of upper vertical wall portions facing each other in the width direction and an upper wall portion connecting between the pair of upper vertical wall portions. and a pair of lower vertical wall portions disposed on the lower side in the vertical direction of the vehicle body with respect to the upper member and facing each other in the width direction and connecting between the pair of lower vertical wall portions. a lower member having a lower wall portion that
4. The subframe for a vehicle according to claim 1, wherein said pair of upper vertical wall portions and said pair of lower vertical wall portions are welded at overlapping portions where they are overlapped correspondingly. The upper member has an upper inclined wall portion between the pair of upper vertical wall portions and the upper wall portion connecting them,
5. The vehicle subframe according to claim 4 , wherein the lower member has a downward inclined wall portion between the pair of lower vertical wall portions and the lower wall portions connecting them.

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